1. Cook the pasta: Bring a large pot of salted water to a rolling boil. Add your chosen pasta and cook according to package directions until al dente. This usually takes about 10-12 minutes. You want the pasta to be tender but still have a slight bite.

2. Drain and cool the pasta: Once the pasta is cooked, drain it thoroughly in a colander. Rinse it with cold water to stop the cooking process and cool it down quickly. This prevents the pasta from becoming mushy and ensures the salad stays fresh. Let it drain well.

3. Prepare the vegetables and protein: While the pasta is cooking, wash and roughly chop the fresh spinach. Halve the cherry tomatoes, thinly slice the red onion, and slice the pitted Kalamata olives if using. Shred or dice your cooked chicken.

4. Whisk the dressing: In a small bowl, combine the olive oil, red wine vinegar, fresh lemon juice, dried oregano, and garlic powder. Whisk vigorously until the dressing is well combined and emulsified. Season with salt and black pepper to taste.

5. Combine the ingredients: In a large mixing bowl, add the cooled pasta, chopped spinach, halved cherry tomatoes, sliced red onion, sliced Kalamata olives, shredded chicken, and crumbled feta cheese.

6. Dress the salad: Pour the prepared dressing over all the ingredients in the large bowl. Toss gently but thoroughly to ensure all the pasta and vegetables are evenly coated with the dressing.

7. Chill and serve: For the best flavor, cover the bowl and refrigerate the pasta salad for at least 30 minutes to allow the flavors to meld. Give it another toss before serving.